<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>Untitled Document</title>
<style>
	#div1 {width: 200px; height: 300px; position: absolute; background: red;}	
</style>
<script>
	window.onload = function()
	{
				document.onmousemove =  function(ev)
				{
							var oEvent = ev || event;
							var oDiv=document.getElementById('div1');
					
							var scrollTop = document.documentElement.scrollTop || document.body.scrollTop;
					
							oDiv.style.left = oEvent.clientX +'px';
							oDiv.style.top = oEvent.clientY + scrollTop +'px';
				};
	};
	</script>
</head>

<body style="height: 2000px">
<div id="div1"></div>
</body>
</html>
